Working dog
A working dog is a dog that was bred or that was trained to perform specific tasks, which usually help a human. Common tasks include herding cattle, but also performing search and rescue operations, hunting, or being employed as guard dogs. Hearing dogs and guide dogs help people who are deaf or blind.
Working Dog Media
Detection dog of the Metropolitan Police patrolling in London
Šarplaninac livestock guarding dogs at work in the Šar Mountains
Search and rescue dog working in Seoul
Historically, drafting dogs were common. A photochrom from the late 19th century showing two peddlers selling milk from a dogcart near Brussels, Belgium.